Physicists at the University of Oslo modeled a split photon and found that trying to crack one light particle in half would not simply create a second photon. In their setup, the result could range from a single photon to several photons, and in an idealized case to an infinite number of light particles.
University of Oslo mirror model
Johannes Skaar and colleagues sent a photon toward a mirror in the model. The front half of the light wave hit first and bounced back in the direction it came from.
They then removed the mirror so the back half could pass through. That switch changed the outcome from one side of the setup to the other, which is where the extra photons appeared in the math.
Physical Review Letters paper
The work was accepted to Physical Review Letters. The calculation showed a superposition of outcomes with different photon counts, so one observer’s view could show a single photon or a vacuum while another view could show a messy eruption of up to bajillions of photons.
Skaar said, “This is a bit strange,” and added, “That is really crazy,” and “you end up with a possibility of several photons, or a bunch of photons.” He also said he hopes to probe the difference more deeply in future work and to explore what would happen if other fundamental particles such as electrons were severed.
Mirror motion and new light
The study suggested that energy fed into the system by moving the mirror could spawn new light particles. Pulling the mirror away more slowly still could create several photons or a bunch of photons.
Daniele Faccio of the University of Glasgow said, “Then you read it, and I enjoyed it,” and “The technique is legit.” He said the result might matter for sensing and measuring applications that use photons, including gravitational wave catchers.
